The present invention relates to a motorised device arranged to move using cyclic motion, and a method of moving thereof. More particularly, but not exclusively, it relates to a micro aerial device.
Recent years have witnessed an increase of research efforts in what is generally referred to as biomimetic robotics. Attracted by the unmatched performance of living systems, roboticists have started applying design principles drawing inspiration from biological evidence. In particular, the agility and maneuverability of living flyers in the air have inspired the development of an increasing number of so-called micro aerial vehicles (MAVs). Besides bio-inspired sensing capabilities and neuro-inspired forms of controllers, there has been a technological push towards the development of biomimetic forms of propulsion, with particular emphasis on flapping wings. Flapping locomotion is superior to other forms of propulsions especially at lower speeds. Unparalleled by man-made vehicles, animals such birds, bats, insects etc are in fact capable of fast forward motion as well as hovering, which is considered one of the most energetically challenging forms of locomotion, since it cannot exploit the accumulated kinetic energy of the body as in forward swimming or flying.
Efficient power usage is fundamental for the development of flapping propellers. One of the limits to flapping propulsion, also faced by living systems especially at larger sizes, is represented by the inertia of the wings. The need to periodically accelerate or decelerate the inertia of the appendices poses serious constraints to the flapping modality. Although the primary interest is doing work against the air, as this directly translates into production of lift and thrust forces, it is not uncommon that accelerating or decelerating wings at relatively high frequencies might require much larger inertial torques than damping ones. This would lead to oversized muscles (and actuators for artificial systems), not to mention other related problems that are known in the art.
One object of the present invention is therefore to address at least one of the problems of the prior art and/or to provide a choice that is useful in the art.